Wiktionary
vb. (context transitive English) To allow entrance into a building from a higher floor by triggering an electronic lock.
Usage examples of "buzz up".
But Randy had taken him up on the offer, looking Buzz up the very day he'd been served his walking papers.
As their names had been on a security list at the door, they'd been waved right through without needing to buzz up and so had no idea of what they were about to face.
You want to return those calls, you just give me a buzz up here and I'll put you through.
Flies would buzz up from the water and the sun would warm the back of the stone.
I'm not much of a ladies' man, but on this particular morning it seemed to me that what I really wanted was some charming girl to buzz up and ask me to save her from assassins or something.
Joe said, 'We'll buzz up there and then afterward when we come back - we'll take in the sights here.